Rasp



L. H. ROBERTS RASP Filed March 27, 1925 2 Sheets-Sheet l INVENTOR.

Leslie 15. Rebel Z3 ATTORNEY.

2 Sheets-Sheet 2 H. ROEERTEB RASP Filed March 27,

, FIG. m

June 22 1926.

FIG, 9

Patented June 252, 19.26.

1,589,9lll

LESLIE H. ROBERTS, OF WICI-IITA, KANSAS.

Application filed March 2'7, 1925.

The invention relates to a tool usel'ul in oil well drilling operations. In drilling oil wells, it frequently happens that the bit will be worked loose and finally drop oil the drill stem and rest on the bottom of the hole then being drilled. From the .S'tlliiitCG oi the ground this is not apparent, consequently as the drilling operations are continued, the up and down motion of the walking beam causes the drill stem to pound and batter on the top of the drill, until the top end of the drill becomes swelled to such an extent that it is impossible to get fishing tools, such as slips and the like, past the knob on the bit, or so that the bit may be removed from the hole. Therefore, the sides of the knob must be cut oil to permit the fishing tools to get hold or the bit. My invention is a rasp-like implement -for this purpose, the character and method of application being more readily understood by reference to the drawings.

In the drawings: Fig. l is a face view of my improved rasp. Fig. 2 is a side view of the rasp seen in Fig. 1. F ig. 3 is a sectional view taken along the line IlI III, Fig. 1 looking in the direction oi the arrows. Fig. 4 is a perspective view or a single rasp tooth as employed in the composite tool. Fig. 5 is a modified form of rasp tooth. Figs. 6, 7 and 8 show vertical sectional views through the improved rasp to disclose varying methods of fastening teeth elements in the body of the rasp. Fig. 9 is a sectional view of the base of an oil well hole, disclos ing how the bit has dropped from the drill stein and under the battering action, previously mentioned,the upper end of the. bit has been swelled. Fig. 10 is a sectional View of the same oil well hole showing my improved rasp in its operative position for cutting oil the sides of the knob-like swelling of the bit. Similar numerals of reference indicate corresponding parts through out all the figures of the drawings.

In the past, tor this purpose, a tool called a rasp has been. employed for this purpose; such tool having teeth merely raised out of the body of the metal, similar to the ordinary rasp. However, a rasp of this type for oil well usageswould necessarily be of considerable length, size and weight and when iii use it would be subject to a very consider able strain and stress at times. It is essen tial, therefere, that the body at ASP.

Serial No. 18,742.

be of such a quality that it will yield con slderably before breaking. Such yielding characteristics, however, are on the contrary very objectionaole tor the formation satisfactory cutting elements, wherein the teeth should be of a quality that will eii ectually cut away the objectionable knob on the bit.

Referring to the drawings: 1 is the body o1 the rasp having a plurality of teeth elements The body 1 is made of a mild steel or material having characteristics pcr it to bend before breaking. Each is termed preferably of air hardened steel. The body of the rasp is pr "'ded with recesses, receptacles or holes of suitable size, shape or conii'guration; each adapted to receive a tooth element of the kind provided. In the preferred form illustrated, suitable holes are punched or drilled in the body of the rasp; the rasp and the teeth elements are then heated, and while hot, the teeth have been inserted into their respective holes in the rasp and positioned to project either straight or at a desired angle, or as shown in Figs. 6, 7 and 8. In Fig. 4 a tooth 2 is shown having a groove 3 on its under side; as assembled in Figs. 6 and 7 it will be noted that by means of a punch, portion of the heated metal 01": the rasp 1 has been driven into the hollow portion 3 of the tooth 2 as disclosed at 4. This binds the tooth 2 within the body of the rasp 1 so that it is impossible to get out. However by use, teeth may become dull and it may be desirable to remove same. In Fig. 7 the hole 5 is shown extending clear through the body of the rasp l. The rasp is then heated and a punch inserted at 5 drives the tooth out for re placement or sharpening and replacement as previously described. In Fig. 8 the shank of the tooth E5 is threaded at 9. and screwed into a threaded hole in the body of the rasp. This type of tooth could be easily unscrewed tor replacement or resharpening.

It will be observed in Figs. 1 and 2 that only about one half of the rasp like device carries teeth elements. The lower portion of Fig. 2 shows a sectional cut taken along the line IIII, Fig. 1 to show the tapering chisel like characteristics of the rasp and the independent teeth elements corresponding to those illustrated in the enlarged detail, such as Fig. 6.

It has been the pi ti'stoin to use rasp lid having teeth the full length of the .rasp. On the upstroke oi' the walking beam, it was necessary to raise the rasp en rely above the bit and on the down stroke it frequently permitted the point of the rasp to strike on top of the bit, which resulted in additional. swelling of the top of the bit and damage to the rasp, itse f. In my invention the lower, or chisel-like portion of the rasp being without teeth, is first permitted to assume the position disclosed in Fig. 10 where the lower chisel-like portion the. rasp has passed the swelled portion of the bit. This blank portion of the rasp then acts as a guide tor the rasp port-ion otthe tool in relation to the hit on which it. is working, therefore the rasp can be worked up and down and never strike on top of. the bit. It is al ays guided to one side of the bit and whenever the teeth strike tl e swelled bit, due to the. momentum of the "asp, the teeth operate to whittle away the swelled portion 8 of the bit.

It will be readily seen that a tool of the type illustrated can be readily repaired. The upper portion of the rasp has a tapering threaded portion (3 for attachment to the chuck, flat faces '7, T being provided to receive a tightening wrench. The section taken along the line 111-111 in Fig. 1 as illustrated in Fig. 8 shows the concave or hollowed out shape of the rasp and tapered end portions of the tool; the tool is made in this shape to best conform to the shape of the hole and to more readily encompass the swelled portion 8 of the bit and thereby more properly chisel such swelled portions away.

Such modifications may be employed as lie within the scope of the appended claims.

Having fully disclosed my invention, what I new claim new and desire to secure by Letters Patent is:

1. A metallic body for a rasp including a chisel-like, blank element at one end, concave in section; a head element at the opposite end as a means for attaelnnent to power operative mechanism; a perforated central section and cutting elements reznovably secured in the perforations through said central portion.

2. A metallic body for a raso including a chisel-like, blank element at one end, con cave in section; a. head element at the opposite end as a. means for attachment to power opeintive mechanism; a perforated central section; a plurality of cutting; blocks, each grooved on its under side; one of said cutting blocks, in each of the periorations, inwardly arranged to provide tooth cutting elements; and parts of the body clc ment driven within the grooves of toothed elements tor engaging purposes.

3. A tool for ehiseling battered drilt-bit portions, having a chisellil-:e blank end portion concave in section adapted for passing and enveloping such a battered drill-bit portion as included within a oil-well casing; and upper toothed cutting portions on said tool adapted "for cutting away said battered portions of the drill-bit, under controlled Vertical movements of the tool and as guided by the lower blank portion of said tool.

LESLIE H. ROBERTS.

the 

